new binpatch(8) binary for ELF kernels

I wrote:

> - Is it still worth to have working (i.e. with ELF support) binpatch(1)?

For now, I've built and put new binpatch(8) binaries
for NetBSD/atari 4.x and 5.0:
ftp://ftp.NetBSD.org/pub/NetBSD/arch/atari/binpatch/
and also update NetBSD/atari FAQ page accordingly.

binpatch-new-4.x.tar.gz: includes /sbin/binpatch binary for 4.x
binpatch-new-5.0.tar.gz: includes /sbin/binpatch binary for 5.x
binpatch-new-5.0.diff: diffs including a new binpatch.c, based on mdsetimage

Note the binpatch.c source is a bit ugly and
maybe it should be brushed up before commit..

Any comments/updates are appreciated.
---
Izumi Tsutsui